The analysis of social networks has become a prominent technique for finding and disseminating information and resources (i.e. those who know things and those who do things). A large number of computer systems and computational and/or mathematical methods have been developed to date to map out, traverse, and identify information and/or resources on people's social networks. Also, a number of systems, also known as social network systems, have been developed to allow people to build and maintain their social networks for various reasons, ranging from socializing to job-hunting to information sharing.